Enzymic synthesis of cocarboxylase in animal tissues

Abstract

SOON after the discovery by Lohmann & Schuster [1937, 1] that cocarboxylase is the pyrophosphate of vitamin B1, there were attempts by various workers to show that the vitamin can be enzymically phosphorylated to cocarboxylase by yeast and tissue preparations. Positive results were claimed with rat liver extracts by Euler & Vestin [1937], with acetone-dried preparations from pig's duodenal mucosa by Tauber [1937], and with avitaminous brain brei by Peters [1937, 1]; whereas Stern & Hofer [1937] failed to obtain synthesis using glycerol extracts from various rat tissues (liver, brain, intestine). Later Lohmann & Schuster [1937, 2] also reported some synthesis with minced pigeon's brain. In all these experiments tissue samples were incubated with vitamin B, in phosphate buffer, boiled and approximately assayed for cocarboxylase by measurement of the CO2 evolution with alkaline-washed yeast and pyruvate.